Ground Freezing — A Viable and Versatile Construction Technique

Effective in all soil and ground conditions, artificial ground freezing has proven many times to be a viable and versatile construction alternative for both open excavation support and groundwater control. The technique is cost-effective where complete groundwater cut-off and in-built ground support are required, where the work is deep, occurs in difficult ground conditions, or where access restrictions limit the use of other displacement-type ground improvement techniques. Ground stabilization at great depths also lends itself well to the use of ground freezing. The technique also works well in ground conditions and situations that are sensitive to vibration or settlement with minor ground losses associated with conventional support methods. In some cases, the protection afforded to adjacent buildings by a monolithic, impermeable structural wall is a significant factor favoring the use of ground freezing. Liquid nitrogen ground freezing has been used successfully for emergency situations in disturbed, displaced, and loose ground conditions, where detailed soil delineation cannot practically be performed. This paper demonstrates the viability and versatility of ground freezing for construction purposes through the presentation of various case histories. In addition, given that the current interest in artificial ground freezing is becoming increasingly focused on environmental remediation, this important - and growing - application is discussed in more detail and illustrated with case histories.